With the growing acceptance of local wireless communication technologies, such as wireless local area network (WLAN) and Bluetooth technologies, numerous computing and communication devices are able to facilitate packet-based, mobile communications. In concert, there is a growing movement to support voice communications over packet-based networks, in addition to the circuit-switched communications supported by existing public switched telephone networks (PSTNs) and cellular networks. The convergence of these trends will result in mobile terminals, such as cellular telephones and wireless personal digital assistants (PDAs), that are capable of communicating using traditional cellular techniques over a cellular network as well as communicating using packet-based techniques over a packet network using local wireless communications. As this convergence matures, voice over packet (VoP) calls will be facilitated via the local wireless communications and circuit-switched calls will be supported via the cellular network for a single mobile terminal.
Unfortunately, local wireless communications are geographically limited, in that the communication range for local wireless communications is much smaller than that provided by cellular services. To ensure the mobility of the mobile terminal, there is a need to be able to transition a call from the local wireless communication interface to a cellular interface when the mobile terminal is no longer able to support local wireless communications. Thus, if a user is participating in a VoP call via the local wireless communications and then moves out the area supported by the local wireless communications, the call would be dropped. However, given the extensive cellular coverage available, there is a strong likelihood that a call could be supported via the cellular network. As such, there is a need for an efficient and effective technique for transferring a call supported via local wireless communications to one supported by cellular communications.